Loeb revealed the embryos were the cause of his breakup with Sofia. He says she cooled on the idea of having kids but he was committed and believed they had already created life.

As TMZ first reported, Vergara doesn't want the embryos destroyed, just frozen indefinitely... in part because she doesn't want to anger her "right to life" fan base. But Loeb calls BS on that -- "In my view, keeping them frozen forever is tantamount to killing them."

Nick says he wouldn't ask Sofia to parent the kids, pay for them, or be involved in any way if she didn't want. He asks, "Does one person's desire to avoid biological parenthood (free of any legal obligations) outweigh another's religious beliefs in the sanctity of life and desire to be a parent."

As for his legal argument, Loeb claims the contract they signed -- which stipulated they both needed to sign off in order for the embryos to be brought to term -- should be voided because (as California law requires) there was no mention of what would happen if they separated.